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Hatfield LA, Hoffbeck RW, Alexander BH, Carlin BP.Hatfield LA, et al.Comput Stat Data Anal. 2009 Jun 15;53(8):3001-3015. doi: 10.1016/j.csda.2008.10.013.Comput Stat Data Anal. 2009.PMID: 20161236Free PMC article.